1. Field of the Invention
This invention relates to data storage and more particularly relates to increasing data integrity in a redundant storage system.
2. Description of the Related Art
Solid-state storage, as well as other forms of data storage media, is subject to failure or data error on specific regions within the solid-state storage. In other instances, an entire device or chip is defective and nonfunctional.
To provide a level of protection against data errors and device failures, often, a plurality of memory devices or storage elements are used, such as in a distributed redundant array of independent drives (“RAID”) or other redundant data system. In a typical RAID system, if a data device fails, the parity devices(s) are used to rebuild the data within the failed device onto a replacement data device. If a parity device fails, the data in the data devices is used to rebuild the parity data in a replacement parity device.
One cause of storage failure is wear-out. Typically, solid-state storage devices have a wear-out mechanism such that a typical memory cell can only be accessed for reading or writing a finite number of times before the memory cell will fail. Therefore, as the number of operations on solid-state storage increase, the wear on the solid-state storage also increases.